Multiple Courses of Antenatal Corticosteroids for Preterm Birth Study (MACS)

In women at 26 to 30 weeks gestation and who are risk for threatened early birth, who have not had their baby by 14 or more days after being given a single course of antenatal corticosteroids (ACS), do repeated courses of ACS every 14 days until 33 weeks' gestational age lower the risk of illness or death in babies compared to repeated courses of placebo. Children are assessed at 2 years and 5 years for neurodevelopmental impairment.

In women at 26 to 30 weeks gestation, who are at increased risk for preterm birth and remain undelivered 14 or more days following a single course of antenatal corticosteroids (ACS), are multiple course of ACS every 14 days until 33 weeks effective in reducing the risk of perinatal or neonatal mortality or significant neonatal morbidity, compared to placebo. 18-24 Month Follow-up: Children (18-24 months corrected gestational age) are assessed with the Bayley Scales of Infant Development (Second Edition) to determine neurodevelopmental impairment. 5 Year Follow-up (MACS-5): Children are assessed using the Child Behaviour Checklist (1 1/2 - 5) and the Behaviour Rating Inventory of Executive Function (Preschool version) to determine neurocognitive function.

MACS-5: At Canadian sites, abnormalities in intelligence and specific cognitive skills (WPPSI-III, Beery: VMI and PPVT-III)

Inclusion Criteria: Women who have previously received one completed course of ACS, at least 14 days ago and continue to be at increased risk of preterm birth Gestational age greater ≥ 26 weeks and gestational age < 31 weeks Exclusion Criteria: Women requiring chronic doses of corticosteroids secondary to medical conditions Women with a contraindication to corticosteroids Women with clinical evidence of chorioamnionitis (temperature ≥ 38°c) Known lethal congenital anomaly (e.g. anencephaly)

Asztalos E, Willan A, Murphy K, Matthews S, Ohlsson A, Saigal S, Armson A, Kelly E, Delisle MF, Gafni A, Lee S, Sananes R, Rovet J, Guselle P, Amankwah K; MACS-5 Collaborative Group. Association between gestational age at birth, antenatal corticosteroids, and outcomes at 5 years: multiple courses of antenatal corticosteroids for preterm birth study at 5 years of age (MACS-5). BMC Pregnancy Childbirth. 2014 Aug 13;14:272. doi: 10.1186/1471-2393-14-272.

Asztalos EV, Murphy KE, Willan AR, Matthews SG, Ohlsson A, Saigal S, Armson BA, Kelly EN, Delisle MF, Gafni A, Lee SK, Sananes R, Rovet J, Guselle P, Amankwah K, Saleem M, Sanchez J; MACS-5 Collaborative Group. Multiple courses of antenatal corticosteroids for preterm birth study: outcomes in children at 5 years of age (MACS-5). JAMA Pediatr. 2013 Dec;167(12):1102-10. doi: 10.1001/jamapediatrics.2013.2764.

Murphy KE, Willan AR, Hannah ME, Ohlsson A, Kelly EN, Matthews SG, Saigal S, Asztalos E, Ross S, Delisle MF, Amankwah K, Guselle P, Gafni A, Lee SK, Armson BA; Multiple Courses of Antenatal Corticosteroids for Preterm Birth Study Collaborative Group. Effect of antenatal corticosteroids on fetal growth and gestational age at birth. Obstet Gynecol. 2012 May;119(5):917-23. doi: 10.1097/AOG.0b013e31825189dc.

Asztalos EV, Murphy KE, Hannah ME, Willan AR, Matthews SG, Ohlsson A, Kelly EN, Saigal S, Ross S, Delisle MF, Amankwah K, Guselle P, Gafni A, Lee SK, Armson BA, Sananes R, Tomat L; Multiple Courses of Antenatal Corticosteroids for Preterm Birth Study Collaborative Group. Multiple courses of antenatal corticosteroids for preterm birth study: 2-year outcomes. Pediatrics. 2010 Nov;126(5):e1045-55. doi: 10.1542/peds.2010-0857. Epub 2010 Oct 18.